Upvoting you because the first statement is right: there is no Linux security. Why? Security at a minimum requires a formal policy of what it's to achieve along with evidence the design meets that policy. Linux never had it. It's track record for flaws goes way in the opposite direction, too. So, it's insecure by default until proven otherwise and that might not even be possible due to complexity.

Combinations of micro/sep kernels and paravirtualized Linux... from L4 projects to commercial like LynxSecure... at least have a start on a security via isolation argument. A start...